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81.
This study aimed to assess food safety in a Vietnamese hospital kitchen with reference to a Japanese hospital, where hygiene management is well implemented. Microbial inspections, including general viable bacteria count, coliform, and Escherichia coli (E. coli) counts were conducted on 10 cookware items, facility equipment, and 14 cooked foods at the two hospital kitchens in Vietnam and Japan. The mean general viable bacteria counts found on cookware and equipment in the Vietnamese hospital kitchen were significantly higher than those in the Japanese kitchen. Furthermore, the frequencies of both general viable bacteria at more than 100 CFU/10 cm2 and coliform/E. coli-positive were significantly higher in the Vietnamese kitchen than in the Japanese kitchen. Coliform bacteria and E. coli were detected in cooked foods in the Vietnamese, but not in the Japanese, hospital kitchen. In light of these results, some key points are suggested to improve the microbial safety status of hospital kitchens in Vietnam.  相似文献   
82.
BACKGROUND: The authors previously found specific mutations of the K-ras gene at codon 12 in the pancreatic juice of 67% of patients (6 of 9) with pancreatic ductal carcinoma, and the detection of these mutations was useful for diagnosis. This study was performed to detect and evaluate K-ras mutations in pancreatic juice from patients with intraductal papillary mucinous tumor of the pancreas, which is considered a low grade malignancy. The results were interpreted from the viewpoint of clinical significance. METHODS: K-ras mutations were examined using seminested polymerase chain reaction analysis combined with restriction enzyme digestion, followed by nonradioisotopic single strand DNA conformation polymorphism. RESULTS: Twelve of thirteen cases (92%) of intraductal papillary mucinous tumor of the pancreas, confirmed histologically (9 adenomas and 4 carcinomas), and 26 of 43 cases (60%) of ductal carcinoma showed specific K-ras gene mutations in the pancreatic juice. Furthermore, 4 of 22 patients (18%) with chronic pancreatitis, followed for more than 1 year without a sign of pancreatic tumor, showed K-ras mutations. In contrast, no mutations of the K-ras gene were detected in the pancreatic juice from 28 normal controls. CONCLUSIONS: K-ras mutations were found in the pancreatic juice of all but one patient with intraductal papillary mucinous tumor of the pancreas, but they were not useful for distinguishing carcinoma from adenoma. The authors concluded that K-ras mutations are not a specific marker for pancreatic neoplasms because similar mutations were detected in the pancreatic juice from patients with chronic pancreatitis. At the present time, the detection of K-ras mutations in pancreatic juice should be used clinically as an adjunct diagnostic modality for pancreatic diseases.  相似文献   
83.
The density and fine structure of the peripheral nerve system in various skin lesions of 64 patients with atopic dermatitis (AD) was quantitatively analyzed by immunohistochemical staining with antibodies directed against protein gene product (PGP) and substance P (SP). The density of PGP-positive peripheral nerves was 2.5 x 10(3) microns2/delta s (delta s = 0.24 mm2 selected area) in early acute lesions, 3.8 x 10(3) microns2/delta s in subacute lesions, 4.9 x 10(3) microns2/delta s in lichenified lesions and 7.1 x 10(3) microns2/delta s in prurigo lesions of AD. The density of nerve fibers in subacute, lichenified and prurigo lesions was significantly higher than in uninvolved skin of AD patients (2.0 x 10(3) microns2/delta s). Electron microscopically, bulging of axons with many mitochondria and a loss of their surrounding sheath of Schwann cells suggests that the free nerve endings in skin lesions of AD are in an active state of excitation. Many pinocytotic vesicles in the periphery of basal keratinocytes facing nerve endings which contained many neurovesicles suggests reciprocal effects between keratinocytes and nerve endings. The number of SP-positive nerve fibers in AD lesions was far less than one-tenth of the number of PGP-positive nerve fibers.  相似文献   
84.
We studied the effects of high intensity resistance exercise training on bone metabolism in 17 young adult Oriental males (23-31 years) by measuring sensitive biomarkers of bone formation and resorption. The subjects were assigned to a training group and a sedentary group. The training group followed a weight training program three times per week for 4 months. In the training group, serum osteocalcin concentration and serum bone-specific alkaline phosphatase activity were significantly increased within the first month after the beginning of resistance exercise training, and the elevated levels remained throughout the training period, while there was no significant change in plasma procollagen type-I C-terminal concentration. Urinary deoxypyridinoline excretion was transiently suppressed and returned to the initial value but was never stimulated during the 4 months. These results suggest that the resistance exercise training enhanced bone formation without prior bone resorption. In the sedentary group, there was no significant difference in bone metabolic markers except plasma procollagen type-I C-terminal, which continuously decreased during the experimental period. There were no significant changes in total and regional bone mineral density in either group. In conclusion, (1) resistance exercise training increased markers of bone formation, while it transiently suppressed a marker of bone resorption, and (2) such adaptive changes of bone metabolism to resistance exercise training occurred during the early period of the training, before changes in bone density were observable through densitometry.  相似文献   
85.
86.
Pimobendan is a new class of inotropic drug that augments Ca2+ sensitivity and inhibits phosphodiesterase (PDE) activity in cardiomyocytes. To examine the insulinotropic effect of pimobendan in pancreatic beta-cells, which have an intracellular signaling mechanism similar to that of cardiomyocytes, we measured insulin release from rat isolated islets of Langerhans. Pimobendan augmented glucose-induced insulin release in a dose-dependent manner, but did not increase cAMP content in pancreatic islets, indicating that the PDE inhibitory effects may not be important in beta-cells. This agent increased the intracellular Ca2+ concentration ([Ca2+]i) in the presence of 30 mM K+, 16.7 mM glucose, and 200 microM diazoxide, but failed to enhance the 30 mM K+-evoked [Ca2+]i rise in the presence of 3.3 mM glucose. Insulin release evoked by 30 mM K+ in 3.3 mM glucose was augmented. Then, the direct effects of pimobendan on the Ca2+-sensitive exocytotic apparatus were examined using electrically permeabilized islets in which [Ca2+]i can be manipulated. Pimobendan (50 microM) significantly augmented insulin release at 0.32 microM Ca2+, and a lower threshold for Ca2+-induced insulin release was apparent in pimobendan-treated islets. Moreover, 1 microM KN93 (Ca2+/calmodulin-dependent protein kinase II inhibitor) significantly suppressed this augmentation. Pimobendan, therefore, enhances insulin release by directly sensitizing the intracellular Ca2+-sensitive exocytotic mechanism distal to the [Ca2+]i rise. In addition, Ca2+/calmodulin-dependent protein kinase II activation may at least in part be involved in this Ca2+ sensitization for exocytosis of insulin secretory granules.  相似文献   
87.
BACKGROUND/AIMS: Corticotropin-releasing hormone (CRH) is a regulator of the hypothalamic-pituitary-adrenal axis and a coordinator of the gastrointestinal response to stress. In addition to its central effects, CRH has peripheral effects on the immune system. CRH is present in several human tissues, such as the brain, spinal cord, adrenal medulla, lung, liver, peripheral blood leukocytes, as well as the gastrointestinal tract. The current study examined the local production of CRH in the normal human colon. METHODS: Normal human colonic tissues obtained by endoscopic biopsy were immunostained with anti-CRH and anti-5-hydroxytryptamine antibody and analyzed for CRH messenger (m)RNA by a reverse-transcribed polymerase chain reaction method and by in situ hybridization. RESULTS: Immunoreactive CRH and CRH mRNA were detected in the colonic mucosal cells in the neighborhood of the base of the crypts. The mucosal cells that expressed CRH mRNA also immunostained with anti-5-hydroxytryptamine antibody. CONCLUSIONS: Normal human colonic mucosal enterochromaffin cells produce CRH. CRH in the colonic mucosa may play a role in the modulation of the intestinal immune system and/or other gastrointestinal functions basally during stressful conditions.  相似文献   
88.
某铅锌冶炼厂湿法炼锌超浸渣组成复杂、酸度高、粒度细,存在部分硅胶,是一种难选物料。采用一粗、一扫、一次空白精选流程,添加硫化钠—丁铵黑药组合剂混合浮选铅、银,可获良好指标。  相似文献   
89.
We have previously described the structures of four novel unconjugated bufadienolides in the ovary of the toad, Bufo marinus. In this study, we report the separation and characterization of three novel bufadienolide conjugates. These compounds were purified by HPLC, and their structures were determined to be 11alpha, 19-dihydroxytelocinobufagin-3-(12-hydroxydodecanoic acid) ester, 11alpha,19-dihydroxytelocinobufagin-3-(14-hydroxy-7-tetra decenoic acid) ester, and 11alpha, 19-dihydroxytelocinobufagin-3-(14-hydroxytetradecanoic acid) ester on the basis of NMR and MS data. Numerous dicarboxylic acid esters of bufadienolides have previously been described, but the three bufadienolide conjugates described in this report differ from previously described esters in that they contain hydroxylated monocarboxylic acids. The function of these three conjugates is not known but they are, like bufotoxins, potent inhibitors of Na+, K+-ATPase and may play a developmental role in the differentiation of toad oocytes.  相似文献   
90.
PURPOSE: Our goal was to characterize the radiologic features of liver metastases from colon cancer with intrahepatic bile duct (IHBD) dilatation. METHOD: Radiologic findings of liver metastases from colon cancer with IHBD dilatation of four patients were compared with pathologic findings. RESULTS: The cause of bile duct dilatation in all cases was due to papillary tumor growth in the bile duct. In two patients, intra-bile duct tumor growth (IBDTG) was observed on imaging. In the other two patients, IBDTG was not observed, but a nontapered abrupt obstruction of a dilated bile duct was seen, corresponding to the microscopically proven papillary tumor growth in the ductal lumen. In three patients who underwent an extensive hepatic resection, there has been no recurrence. In one patient who had a nonanatomic limited resection, a recurrence was seen 1 year after surgery. CONCLUSION: When liver tumor with IBDTG is suspected on imaging, liver metastases should be considered in the differential diagnosis besides hepatocellular carcinoma or cholangiocellular carcinoma. Careful preoperative assessment for IBDTG by imaging is essential to determine the extent of surgical resection.  相似文献   
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